Selecting green cover species in the under-trellis zone of Lower Austrian vineyards

The ongoing climate change implies an increasing mean air temperature, which is signified by weather extremes or sudden changes between drought and local heavy rainfalls. These changing conditions are especially challenging for the established grapevine varieties growing under cool climate conditions due to an increased risk for fungal diseases like downy mildew (DM) and Botrytis bunch rot (BBR) as well as for grape sunburn. To meet that demand, the scope of most grapevine breeding programs is the selection of mildew fungus-resistant and climatic adapted grapevines with balanced, healthy yield and outstanding wine quality.

Among the Moscato grapes, Moscato Giallo is a winegrape variety characterized by a high content of free and glycosylated monoterpenoids, which gives very aromatic wines. The aromatic bouquet of Moscato Giallo is strongly influenced by the high concentration of linalool, geraniol, linalool oxides, limonene, α-terpineol, citronellol, HO-trienol, HO-diols, 8-Hydroxylinalool, geranic acid and β-myrcene, that give citrus, rose, and peach notes.

In Chile there is a dry farming area known as a traditional wine region, where varieties brought by the Spanish conquerors still persist. These varieties, in general, are cultivated under traditional systems, with low use of technical and economic resources, and low profitability for their grapes and wines. In this region, as in other wine grape growing areas, climatic conditions have changed significantly in recent decades. In particular, the occurrence of spring frosts, when bud break has already begun, have generated significant losses for these growers.

Grapevine pruning is one of the most important practices in the vineyards. Winegrowers use it to provide the vines the shape needed, or to maintain it once achieved, and also to balance vegetative growth and fruit production. In the last decades, careless pruning has been blamed, among other factors, as responsible of the vineyard decay that is been observed even in young vines. However, to our knowledge, there is a lack of systematic research trying to elucidate to which extent the pruning method used affects plant development or its susceptibility to grapevine trunk diseases (GTD). Within this context, the aim of this work is to study the influence of different pruning method strategies on the development of field-planted young vines.

Over the last years, due to climate change, several red wines, such as the Sangiovese wines, have been often subjected to loss of clarity due to the formation of deposits of fine needle-shaped crystals. This phenomenon turned out to be due to an excess of quercetin (Q) and its glycosides (Q-Gs) in wines. These compounds are synthesized to a large extent when grapes are excessively exposed to UVB radiations in vineyards[1]. Unfortunately, it is not easy to predict the degree of Q precipitation because its solubility strongly depends on the wine and matrix composition[2].